With ever-increasing use of cards of various types for carrying information, for identification, and for authorizing financial transactions, there has also been an increased incidence of fraud and forgery in which counterfeit cards are used. The annual cost of credit-card forgery alone has been reported in the hundreds of millions of dollars ("Business Week" Apr. 4, 1994, page 95), despite many attempts to prevent fraud by various means to authenticate credit cards. Cards other than credit cards are used to carry coded information about the identity of individuals, their licenses to drive automobiles or to operate other equipment, their authorization for access to restricted facilities, their eligibility for various services such as medical care, etc. Such "credit card" size data storage articles include identification and security cards (driver's license, employee ID cards, badges, access control cards, immigration cards, etc.), financial and transaction cards (credit cards, debit cards, ATM cards, phone cards, subway cards, etc.), data cards (medical information, insurance and benefit information cards, car registration, etc.), telecommunication technician test cards, smart cards, computer memory cards, etc. Such cards may be subject to the same methods of counterfeiting as those used for credit cards. With technical advances and easy access to technologies such as personal computers, graphic software, image scanners, laminating equipment, credit card impact printers, instant-print cameras, and other card-making materials and equipment, a counterfeiter can easily forge such cards including most visible security features employed on them. Examples of such visible security features which can be replicated by counterfeiters are patterned backgrounds, holograms, pictures, and fingerprints. Therefore, there is a need to provide additional security features that cannot be duplicated with technologies based on visible features, and a need to provide automatic authentication that does not rely on human subjective judgment.
The current installed base of credit card readers in the U.S. and Canada alone is estimated at over 40 million units according to the American Bankers Association. World-wide installations of all types of card readers easily exceed billions of dollars in equipment value. Therefore, it is highly desirable to provide an add-on device to the existing readers that can detect invisible security features.
Thus there is an important and continuing need to prevent fraud based on counterfeit data storage articles, particularly data storage articles in the form of a card. At the same time, business enterprises and especially retail establishments, have invested in millions of card readers and/or scanners. It is highly desirable to have methods and apparatus for authentication of cards that would not require businesses to replace their existing card readers or existing scanners with a new type of authenticating reader or scanner.